Structural Studies on Crystals of Ribosomal Particles

Abstract

Ribosomes, the universal cell organelles on which protein biosynthesis takes place, consist of two subunits which associate upon initiation of the biosynthetic process. Each ribosomal subunit is a defined assembly of proteins and ribonucleic acid chains. A typical bacterial ribosome, e.g. that of Escherichia coli, has a molecular weight of 2.300.000 Dalton. Its large (50S) subunit is of 1.450.000 Dalton and consists of 33 different proteins and 2 RNA chains. The small subunit (30S) is of 850.000 Dalton and contains 21 proteins and 1 RNA chain (Wittmann, 1982).